Aerial of low directional effect and horizontal polarization



Gd. 15, 1935. GOURlAUD 2,017,121

AERIAL OF LOW DIRECTIONAL EFFECT AND HORIZONTAL POLARIZATION Filed April 4, 1933 ATTORNEY Patented Oct. 15, 1935 UNITED STATES ATENT OFFICE AERIAL OF LOW DIRECTIONAL EFFECT AND HORIZONTAL POLARIZATION Michel Gouriaud, Paris, France, assignor to Compagnie Generale de Telegraphic Sans Fil, Paris,

France Application April 4, 1933, Serial No. 664,379 In France April 14, 1932 4 Claims.

mitter station extends to a distance of from 100 to 200 kilometers (60 to 120 miles).

On the other hand, a simple horizontal antenna involves the inconvenience of possessing directional powers and properties.

The present invention (system Gouriaud) is concerned with a horizontally polarized lowdirectivity antenna, which, by virtue of its properties, is more particularly applicable to radio broadcasting work.

In the drawing, Figure 1 illustrates an embodiment of the present invention; Figure 2 illustrates in vector form the fields set up by theantennae of Figure 1 at a distance from the antenna structure; and Figure 3 shows a field diagram obtainable from the arrangement of Figure l.

The aerial properly so-called consists of a horizontal square, the four sides of which, are insulated at their ends A, B, C, D. The length of each of the sides is equal to one-half wave.

The feeding of this aerial is effected at the ends of (or across) one diagonal as indicated in Figure 1. For this purpose there is stretched out along the diagonal CD a double conductor, and each of these is broken in the middle (at points a and b) by an' insulator. The feeder brought from the transmitter is connected with the feeding system in the center of the square, in that one of the conductors of the feeder is united at the same time with elements D and b0, and the other conductor of the feeder with the elements (1.0 and bD, or inversely. It will be seen that the potential furnished by the feeder at points a and b is symmetric in reference to ground, hence, the currents at each instant are equal and of like sense in the four sides of the aerial.

Taking a position on the vertical at the midpoint of the antenna the fields set up by the sides AC, BD, and AD, BC, respectively, neutralize one another.

If, on the contrary (see Figure 2), taking a position in the plane of the antenna in direction OH, the field set up by the sides AD and BC is of zero value. The field produced by the side ED is equal to h as well as that produced by the side AC. These two fields become added to each other arithmetically, seeing that the currents are opposite, but the difference in the distances to be covered is equal to one-half wave. Hence, the resultantfield is equal to Zn.

In the direction OK the field set up by the sid AD is equal to The field produced by the side AC is likewise equal to h It would be opposite since the current looking in the direction OK is opposite. However, inasmuch as the distance to be covered is over A 2 /5 the phase displacement angle is or 1.71 or 306 degrees. The geometric resultant of the two fields is 1.2511. (Figure 2) The resultant of the field set up by the sidesBC and ED is equal and of identical sense. The field obtained, finally, is 2.5%.

The field diagram is represented in Figure 3. It will be seen that there are still two slightly favored or preferential directions, but the difference is too small to be sensible in practice.

What is claimed is:

1. Horizontally polarized antenna comprising four conductors forming a square in a horizontal plane and insulated from each other, the length of each conductor being equal to one-half length of the transmitted wave, a radio frequency 40 source having two output terminals and provided with means for simultaneously delivering at all instances on both respective terminals equal but sign opposed potentials, means for feeding a pair of opposed square sides from one of said terminals, and means for simultaneously feeding the other pair of square sides from the other terminal of said source.

2. Antenna comprising four conductors insulated from each other forming a square in a horizontal plane, a feeding conductor attached to each of said conductors, a feeding line having two conductors each respectively connected to two of the said feeding conductors attached to opposed sides of the said square, and a source of potential difference which is symmetric with respect to ground connected with said feeding line.

3. An antenna in accordance with claim 2, characterized in this that two feeding conductors attached to two adjacent sides 'of the square 7 are connected to a common insulator and aligned to extend across ai'diagonal'ofthe square,"the

other two feeding conductors being connected and aligned in a similar manner, and said two pairs of conductors extending along two parallel lines. 7 V V 1 other, and means for feeding adjacent conductors of said square out of phase with respect to one another and opposite conductors of said square NIICHEL GOURIAUD.

in phase. 10 

